Modelling in HD(CP)²

In the first funding phase, the HD(CP)² model (ICON-LEM) was developed from an existing ICON non-hydrostatic core. In the second phase of the project, the focus shifts from model development to adapting the model to different next generation high-performance computing hardware. This is done to improve the computational efficiency (i.e. time to solution) and is fostered by the collaboration between the DKRZ (Deutsches Klimarechenzentrum) and the FZJ (Forschungszentrum Jülich).

This figure gives an overview of the structure of the second funding period of HD(CP)².The individual S-projects are supported by model simulations (M) and observations (O), making M and O fundamental cornerstones of the whole project.

This certain topic is addressed in work package 1 of the M module (see figure on the right), "Optimization of sustained application performance". The M module serves as one of the cornerstones of the project, as the envisaged high-resolution simulations are not possible without the technical work that is done in this part of the project. A central task of work package 2 is the implementation of a new sub-grid cloud cover scheme that enables hindcast simulations over the Tropical Atlantic (TA) and Northern Atlantic (NA) area. Moreover, the simulation model will be enhanced by implementing and improving online diagnostic functionality, which is done in work package 3. Generally, the M module conducts the production of simulations with the ICON-LEM (Large-eddy model) as are requested by the six scientific projects of HD(CP)². These high-resolution simulations (O of 100 m) are performed over the entire Germany domain (DE), as well as for TA and NA (work package 5).Work package 4 continues with the development of the end-to-end workflow of HD(CP)² simulations and the adaptation to support an automated execution chain that combines pre- and post-processing tools as well as a basic data management. The resource planning in order to successfully perform those ambitious model runs is done in work package 6.

The scientific projects within HD(CP)² are assisted in using these tools to conduct additional model runs in project-internal workshops.

A HD(CP)² model simulation of liquid cloud water, wind speed and vorticity over Germany. Liquid cloud water is shown in white, cloud ice in pink, and rainfall in blue. Wind speed is depicted with streams lines, where purple lines indicates low and yellow lines high wind speeds.

The HD(CP)² model and its scheduled simulations will be extremely ambitious regarding computing resources and data space. Moreover, the model enhancement will include the implementation of advanced online diagnostic tools for 3D visualization of features directly during the experiment runs.This is addressed in work package 3 "Model diagnostics", located at the ZIB.

This animation features several visualizations based on simulations carried out for different domains and at different resolutions - ranging from a global setup of the atmosphere model ICON at a resolution of 5 km to the large eddy version ICON-LEM at 150 m resolution. Visualization: Niklas Röber (DKRZ) Simulations: Matthias Brück (MPI-M), Daniel Klocke (DWD) and Philipp Neumann (DKRZ) Principal Investigators: Bjorn Stevens (MPI-M) and Joachim Biercamp (DKRZ). ICON is a joint development of the German Weather Service (DWD) and the Max Planck Institute for Meteorology (MPI-M).